WO-2026096186-A1 - VARIABLE RESISTANCE NETWORK

Abstract

A variable resistance network includes a plurality of resistance modules electrically connected in series along an electrical conduction path between an input electrical node and an output electrical node. The variable resistance network includes a plurality of relay modules electrically connected to control activation and deactivation of respective ones of the plurality of resistance modules. The variable resistance network includes a controller electrically connected to each of the plurality of relay modules. The controller is configured to transmit electrical control signals to each of the plurality of relay modules to independently control operation of each of the plurality of relay modules and correspondingly control activation and deactivation of the plurality of resistance modules. The variable resistance network is implementable for controlling radiofrequency signal return pathways from one or more electrodes within a plasma processing chamber.

Inventors

• LIU, CHANG
• CARON, James, E.
• SHARETSKY, Aleksander

Assignees

• LAM RESEARCH CORPORATION

Dates

Publication Date

20260507

Application Date

20251010

Priority Date

20241031

Claims (20)

1. 1. A variable resistance network, comprising: a plurality of resistance modules electrically connected in series along an electrical conduction path between an input electrical node and an output electrical node; a plurality of relay modules electrically connected to control activation and deactivation of respective ones of the plurality of resistance modules; and a controller electrically connected to each of the plurality of relay modules, the controller configured to transmit electrical control signals to each of the plurality of relay modules to independently control operation of each of the plurality of relay modules and correspondingly control activation and deactivation of the plurality of resistance modules.
2. 2. The variable resistance network as recited in claim 1, wherein each of the plurality of resistance modules includes at least one fixed electrical resistor.
3. 3. The variable resistance network as recited in claim 2, wherein at least one of the plurality of resistance modules includes a plurality of fixed electrical resistors.
4. 4. The variable resistance network as recited in claim 3, wherein the plurality of fixed electrical resistors includes at least two fixed electrical resistors electrically connected in series.
5. 5. The variable resistance network as recited in claim 3, wherein the plurality of fixed electrical resistors includes at least two fixed electrical resistors electrically connected in parallel.
6. 6. The variable resistance network as recited in claim 3, wherein the plurality of fixed electrical resistors includes at least two fixed electrical resistors electrically connected in series and at least two fixed electrical resistors electrically connected in parallel.
7. 7. The variable resistance network as recited in claim 1, wherein each of the plurality of resistance modules has an input and an output, the input of a first resistance module in the plurality of resistance modules electrically connected to the input electrical node, the output of a last resistance module in the plurality of resistance modules electrically connected to the output electrical node, and wherein each of the plurality of relay modules has an input electrically connected to the input of a respective one of the plurality of resistance modules and an output electrically connected to the output of said respective one of the plurality of resistance modules.
8. 8. The variable resistance network as recited in claim 7, wherein each of the plurality of relay modules is configured to form a low resistance electrical conduction path around said respective one of the plurality of resistance modules to deactivate said respective one of the plurality of resistance modules, and wherein each of the plurality of relay modules is configured to block the low resistance electrical conduction path around said respective one of the plurality of resistance modules to activate said respective one of the plurality of resistance modules.
9. 9. The variable resistance network as recited in claim 1, further comprising: a printed circuit board to which the plurality of resistance modules are electrically connected, the electrical conduction path between the input electrical node and the output electrical node formed through the printed circuit board.
10. 10. The variable resistance network as recited in claim 9, further comprising: a cooling system disposed in thermal connection with the plurality of resistance modules.
11. 11. The variable resistance network as recited in claim 10, wherein the cooling system includes a heat transfer plate in thermal connection with the plurality of resistance modules.
12. 12. The variable resistance network as recited in claim 11, wherein the cooling system includes one or more of a fan disposed to direct air flow over the heat transfer plate and a tube disposed to direct cooling fluid through the heat transfer plate.
13. 13. A plasma processing system, comprising: a plasma processing chamber; an electrode disposed within the plasma processing chamber; and a variable resistance network electrically connected between the electrode and a reference ground potential, the variable resistance network including a plurality of resistance modules electrically connected in series, the variable resistance network also including a plurality of relay modules electrically connected to control activation and deactivation of respective ones of the plurality of resistance modules, the variable resistance network also including a controller electrically connected to each of the plurality of relay modules, the controller configured to transmit electrical control signals to each of the plurality of relay modules to independently control operation of each of the plurality of relay modules and correspondingly control activation and deactivation of the plurality of resistance modules.
14. 14. The plasma processing system as recited in claim 13, wherein each of the plurality of resistance modules has an input and an output, each one of the plurality of resistance modules providing a different fixed electrical resistance along an electrical conduction path through the variable resistance network, and wherein each of the plurality of relay modules has an input electrically connected to the input of a respective one of the plurality of resistance modules and an output electrically connected to the output of said respective one of the plurality of resistance modules.
15. 15. The plasma processing system as recited in claim 14, wherein each of the plurality of relay modules is configured to form a low resistance electrical conduction path around said respective one of the plurality of resistance modules to deactivate said respective one of the plurality of resistance modules, and wherein each of the plurality of relay modules is configured to block the low resistance electrical conduction path around said respective one of the plurality of resistance modules to activate said respective one of the plurality of resistance modules.
16. 16. The plasma processing system as recited in claim 13, further comprising: a radiofrequency signal filter electrically connected between the variable resistance network and the electrode, the radiofrequency signal filter configured to block at least one specified range of signal frequency from reaching the variable resistance network.
17. 17. The plasma processing system as recited in claim 13, wherein the electrode includes multiple electrode zones, the multiple electrode zones electrically separated from each other, wherein said variable resistance network is one of multiple variable resistance networks, each one of the multiple variable resistance networks electrically connected between a respective one of the multiple electrode zones and the reference ground potential, each of the multiple variable resistance networks including a corresponding plurality of resistance modules electrically connected in series, each of the multiple variable resistance networks also including a corresponding plurality of relay modules electrically connected to control activation and deactivation of respective ones of the corresponding plurality of resistance modules, and wherein the controller is electrically connected to each relay module of the corresponding plurality of relay modules within the multiple variable resistance networks, the controller configured to transmit electrical control signals to each relay module to independently control operation of said relay module.
18. 18. A method for providing controlled variable electrical resistance, comprising: electrically connecting a plurality of resistance modules in series along an electrical conduction path between an input electrical node and an output electrical node; electrically connecting a plurality of relay modules to control activation and deactivation of the plurality of resistance modules, such that a different one of the plurality of relay modules is electrically connected to control a correspondingly different one of the plurality of resistance modules; and setting a cumulative resistance along the electrical conduction path between the input electrical node and the output electrical node by controlling each of the plurality of relay modules in an independent manner to activate or deactivate the corresponding one of the plurality of resistance modules to which said each of the plurality of relay modules is electrically connected to control, wherein activation of a given one of the plurality of resistance modules causes an electrical resistance of the given one of the plurality of resistance modules to be imparted along the electrical conduction path between the input electrical node and the output electrical node, and wherein deactivation of the given one of the plurality of resistance modules causes the electrical resistance of the given one of the plurality of resistance modules to not be imparted along the electrical conduction path between the input electrical node and the output electrical node.
19. 19. The method as recited in claim 18, further comprising: electrically connecting the input electrical node to an electrode within a plasma processing chamber; and electrically connecting the output electrical node to a reference ground potential.
20. 20. The method as recited in claim 19, further comprising: filtering electrical signals between the electrode and the variable resistance network to block at least one specified range of signal frequency from reaching the variable resistance network.

Description

Variable Resistance Network by inventors Chang Liu, Janies E. Caron, Aleksander Sharetsky Background of the Invention [0001] Plasma processing systems are used to manufacture semiconductor devices, e.g., chips/die, on semiconductor wafers. In the plasma processing system, the semiconductor wafer is exposed to various types of plasma to cause prescribed changes to a condition of the semiconductor wafer, such as through material deposition and/or material removal and/or material implantation and/or material modification, etc. During plasma processing of the semiconductor wafer, radiofrequency (RF) signals are transmitted through a process gas within a chamber to impart RF power into the process gas and correspondingly transform the process gas into the plasma in exposure to the semiconductor wafer. Reactive constituents of the plasma, such as radicals and ions, interact with materials on the semiconductor wafer to achieve a prescribed effect on the semiconductor wafer. In some plasma processing systems, the RF signals are transmitted from an electrode structure within the chamber to the processing region in order to transform the process gas into the plasma in exposure to the semiconductor wafer. It is within this context that various embodiments described herein arise. Summary of the Invention [0002] In an example embodiment, a variable resistance network is disclosed. The variable resistance network includes a plurality of resistance modules electrically connected in series along an electrical conduction path between an input electrical node and an output electrical node. The variable resistance network also includes a plurality of relay modules electrically connected to control activation and deactivation of respective ones of the plurality of resistance modules. The variable resistance network also includes a controller electrically connected to each of the plurality of relay modules, the controller is configured to transmit electrical control signals to each of the plurality of relay modules to independently control operation of each of the plurality of relay modules and correspondingly control activation and deactivation of the plurality of resistance modules. [0003] In an example embodiment, a plasma processing system is disclosed. The plasma processing system includes a plasma processing chamber. The plasma processing system also includes an electrode disposed within the plasma processing chamber. The plasma processing system also includes a variable resistance network electrically connected between the electrode and a reference ground potential. The variable resistance network includes a plurality of resistance modules electrically connected in series. The variable resistance network also includes a plurality of relay modules electrically connected to control activation and deactivation of respective ones of the plurality of resistance modules. The variable resistance network also includes a controller that is electrically connected to each of the plurality of relay modules. The controller is configured to transmit electrical control signals to each of the plurality of relay modules to independently control operation of each of the plurality of relay modules and correspondingly control activation and deactivation of the plurality of resistance modules. [0004] In an example embodiment, a method is disclosed for providing controlled variable electrical resistance. The method includes electrically connecting a plurality of resistance modules in series along an electrical conduction path between an input electrical node and an output electrical node. The method also includes electrically connecting a plurality of relay modules to control activation and deactivation of the plurality of resistance modules, such that a different one of the plurality of relay modules is electrically connected to control a correspondingly different one of the plurality of resistance modules. The method also includes setting a cumulative resistance along the electrical conduction path between the input electrical node and the output electrical node by controlling each of the plurality of relay modules in an independent manner to activate or deactivate the corresponding one of the plurality of resistance modules to which said each of the plurality of relay modules is electrically connected to control. Activation of a given one of the plurality of resistance modules causes an electrical resistance of the given one of the plurality of resistance modules to be imparted along the electrical conduction path between the input electrical node and an output electrical node. Deactivation of the given one of the plurality of resistance modules causes the electrical resistance of the given one of the plurality of resistance modules to not be imparted along the electrical conduction path between the input electrical node and an output electrical node. [0005] In an example embodiment, a method is disclosed for controlling radiofrequency s